F.O.A.M. BLOG

Las Vegas FOAM Blog is dedicated to sharing cutting edge learning with anyone, anywhere, anytime. We hope to inspire discussion, challenge dogma, and keep readers up to date on the latest in emergency medicine. This site is managed by the residents of Las Vegas’ Emergency Medicine Residency program and we are committed to promoting the FOAMed movement.

Why did we need a new sepsis definition?It has been recognized, in one form or another, since ancient Greece, that some patients will get symptoms of an infection and over a few days get better, while some will get symptoms of an infection, then over a few days get multi-organ system failure and die. In the 2000 years since, it has proven surprisingly hard to predict which patients are going to fall into that later category, in other words which patients are going to develop, or are already in the early stages of, “sepsis.”1 Broadly speaking, we can define “sepsis” as a severe infection associated with organ dysfunction.2 But getting any more specific than that has proven problematic. The upshot is that, as of 2016, we still have no “gold standard” test or set of criteria by which to define sepsis.3

The first attempt at a universal definition and set of clinical criteria for sepsis came in 1991, when a panel of experts from the American College of Chest Physicians and Society of Critical Care Medicine convened in Chicago to put their heads together and produce an “expert consensus.”4 Prior to that, there was no universally accepted definition of “sepsis,” which led to great heterogeneity in the methods and findings of different research groups, as well as consternation among clinicians trying to care for patients. In the years since 1991, specifically through repeat conventions in 2001 and 2012, that expert-consensus definition has been refined and revised into the form my generation learned in medical school, outlined below. Whether or not it was the intention of those conventioneers back in 1991, their core definition, and its underlying assumption that SIRS in the setting of infection progresses to “severe sepsis,” which progresses to “septic shock,” which progresses to “multisystem organ dysfunction,” has become dogma in medical education.5

And that presents a problem, because as all of us working in the ED know, the current sepsis definition is not great.

The 1991 consensus definition, and all its iterations since, were meant not just to aid researchers, but to serve as part of an effort to raise awareness and promote early recognition of sepsis; this eventually became the groundwork for the Surviving Sepsis Campaign. To that end, the definitions were designed to be broad and highly sensitive.3 And that they are (albeit maybe not as sensitive as we once thought6) but at the expense of specificity. A tremendous proportion of ICU patients meet SIRS criteria, with or without infection.7 As ED residents, we all see multiple patients every shift that meet SIRS criteria, be it from dehydration, a common cold, anxiety, the flu, meth…. The question becomes do they also have a “suspected infection,” and therefore need broad-spectrum antibiotics and admission? It’s often extremely hard to say, and ends up being a subjective and provider-dependent decision. How many times have you admitted a patient from the ED with a vague diagnosis of “rule out sepsis,” because you knew they were nonspecifically sick enough to need observation, and knew you could use the SIRS criteria as ammunition in negotiating with the hospitalist? How many times have you admitted a patient to the ICU with shock but no obvious infection only to find out their diagnosis became “septic shock” because the chest x-ray showed a questionable pneumonia, or the urinalysis had some bacteria in it? The legal and reimbursement systems in the United States force us to assign discrete, billable diagnoses to patients, and “sepsis,” “severe sepsis,” and “septic shock,” have become some of our most useful catch-alls, albeit to the likely detriment of accuracy and antibiotic stewardship.

Sepsis 3 is an attempt to improve this situation. It redefines “sepsis,” using an ICU-oriented clinical tool called the SOFA (Sequential Organ Failure Assessment) score, eliminates the concepts of “SIRS” and “severe sepsis,” and in homage to our current understanding of the disease’s complex pathophysiology, generally tries to move away from the idea of sepsis as a disease with a predictable, linear progression.8-10

Does the specific definition really matter that much?For doing and interpreting studies (in other words figuring out what treatments work), yes it matters tremendously. Does a 6-year-old dying of meningococcemia really have the same disease as a 50-year-old with a pulse of 95, WBC 12.5 and negative blood cultures but a little chest x-ray haziness? It all depends on how you define the disease, and, for better or worse, according to our current definition the answer to that question is, “yes.” Without an accurate, useful definition, you can’t even research sepsis well. How do you know the patients in that “CVP-guided fluid management in sepsis“ study you did really belonged in the experimental group? How do you know the mice in the research lab on which you’re testing novel drugs really have sepsis, or are in the same stage of their sepsis? And as clinicians, how can we trust that the results of any of these studies translate to our patient populations?

To identify patients at particularly high risk of mortality or a long ICU stay, bedside providers should look for any of the qSOFA criteria:

qsofa: R> 22, altered mental status, SBP< or = 100

So is this new definition going to help the situation?There is an argument to be made that, until we have some sort of new biomarker specific to sepsis, or some fundamental shift in our understanding of the disease that makes a new biomarker unnecessary, any attempt to define sepsis by rearranging physical exam findings, vital signs and current lab tests is going to be like rearranging the three primary colors in a futile attempt to produce a novel color. It won’t work – the current tools are too limited. Imagine trying to define DKA without the concept of insulin.

But that argument aside, the answer to this question from an ED perspective is…probably not. This new sepsis definition is remarkably out-of-synch with how we work up sepsis at UMC: you cannot calculate a SOFA score without an arterial blood gas (we practically never get those on non-intubated patients), and the score is based on the notion that dopamine is everyone’s first choice of pressor in septic shock (I have yet to use dopamine in two years of residency). These are going to be real problems if national quality-measures and reimbursement end up linked to having “properly documented a SOFA score.”

Meanwhile, the qSOFA score, the suggested tool for frontline providers like us, seems doomed to be proven non-inferior to clinical gestalt. What we need in the ED is a tool to help us make clinical decisions on intermediate-risk patients for early sepsis; Sepsis 3 seems geared towards identifying only the sickest patients that need ICU care right this minute. A boon for researchers, but probably not for us.

On a super practical note, this new definition takes away our aforementioned SIRS criteria ace-in-the-hole when negotiating a gestalt-based admission with a reluctant hospitalist. As for whether or not this turns out to be a good thing in the long run for costs and patient safety, time will tell.

On the upside, for those of us loath to administer broad-spectrum antibiotics to patients who almost certainly don’t need them, but who technically meet SIRS criteria, we now have ammunition for an argument not to do so.

What’s the initial reaction to this in the rest of the medical community?Mixed.10-13 There were 31 medical societies involved in the creation of the new sepsis definition, but only a small handful from the United States, and only one emergency medicine society (the European Society of Emergency Medicine). As of today, it has not been endorsed by ACEP, SAEM, or any other American emergency medicine society. Chest, the official journal of the American College of Chest Physicians (co-creators of the original 1991 consensus definition), has published a pretty critical editorial.11 Initial response in the FOAM world has been skeptical at best.7,14-16

When I go into my next ED shift, do I need to do something differently because this new sepsis definition now exists?No you don’t. It’s probably a good idea to let this hash itself out in the literature and administrative worlds first. Keep following your hospital or group’s established sepsis protocols, and keep using the same lab tests and road-tested gestalt you’ve been using to pick the sickest needles out of the haystack.

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Las Vegas EM FOAM Blog

A FREE AND OPEN-ACCESS MEDICAL EDUCATION BLOG BY THE RESIDENTS AND FACULTY OF LasVegasEM.

The information contained in this blog is for educational puposes only and is not intended to advocate specific medical practices. All opinions are our own and do not imply endorsement by our hospital or school of medicine. Any reference to patients has been redacted or intentionally altered to make identification impossible.

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